Diesel heater plugs

Having didficulty sorting the heater plugs. On a late series IIA, Plugs wired in series. Using the multimeter i have chaeck that there is continuity through the plugs, i'm assuming this means the plugs are ok! i have replaced the resistor and the instrument panel lamp. I have checked that power goes to the resistor but the lamp does not light at all, i have with the multi meter checked the cables.

Any other ideas why it doesn't work?
Thanks

do the plugs not work or has the bulb 'popped?' use decent battery to try heating plugs. If they work, they warm up (oops -that's a bit obvious)- remove from bores and ensure decent contact between them and engine to check (NB (nota bene) - adding a new (extra) earth strap always helps - Polo eatrhs from 'head to body-gets rid of one possibility - cheap and fittings there) to check. May be old wiring or 'timing solenoid' (mine is 'turn of the key, relay and wristwatch') If starter turns,contact is good. If all plugs fail, problem is usually 'upstream'. I'm no expert but if all plugs fail it's unusual (IME). Rewire plugs (cheapest option) to remove intermittent wire fault, add more earths, direct supply from battery will show either feed problem or prob between batt and plugs. This narrows it then to 'timed relay' or feedfrom ignition. Or a fault I'venever seen. I'm crap at electronics butif you renew all wires (not a lot) at least you remove one possibility from equation (My 5-cyl Passat (90mph in 2nd anyone?) had intermittent wire fault. Discovered whenI watrched enginerun in the dark(sparks seen to 'head').
HTH. If you stillhaveprob after oing this, post here.
While I'm here, I'djustliketo congratulate my member on attaining full status.If this (and I) am of no help I'd liketo know. As I work from a 'full head' and 'empty pockets' I often have to start with the cheapest thing first (which is why my only Freelander advice is always. "sell that POS"). A multimeteronly costs £20 or less and should be your first purchase(after ddecent tools -an Britool & Facom cost far less than a:you think & b: running back to Halfords for replacements..)
HTH

Thanks, I removed all the plugs and one did not heat up, this one was different to the others. As the wiring was also a bit ropey i decided to fit the conversion kite which now seems to work much better. The lamp comes on bright and stays bright, shouldn't it go dim after about 20 seconds? or come on dim and go brighter?
Thanks

Your heater plugs are wired in series like old xmas tree lights, if one dies they all die. Rewire them in parallel, this makes the heater system much more reliable, ten minutes work. If one is faulty the other three will still work. A diagram for this modification should be easy to find online, if not contact me and I'll draw one up for you.